Mental distress and subsequent use of anxiolytic drugs--a prospective population-based cohort study of 16,000 individuals.

Aims: To study the relationship between mental distress and later use of anxiolytic drugs, taking into account potential confounders such as lifestyle and socioeconomic factors.
Methods: In a prospective cohort study, data from population-based health surveys from three Norwegian counties (2000-01) were linked to data from the Norwegian Prescription Database (NorPD) (2004-07). In the surveys, 9,386 men (43.1% of those invited) and 11,244 women (52.4%) participated. The two age cohorts were 40 and 45 years old (cohort 1) and 60 years old (cohort 2). Participants in each age group were divided into quartiles (Q1-Q4) separately for men and women according to the degree of mental distress, measured by increasing Hopkins Symptom Checklist-10 score (HSCL-10 score) at baseline. Multivariate logistic regression was performed to assess predictors of anxiolytic drug use.
Results: At baseline: Increasing HSCL-10 score was associated with: increasing use of specified prescribed drugs, poor health, ever having sought help because of mental distress, musculoskeletal pain, being married or in partnership, low educational level, receiving disability pension and current smoking (except for women 60 years old). Predictors found: There was a graded positive relationship between HSCL-10 score at baseline (2000-01) and the chance of a prescription of anxiolytics during follow-up (2004-07) in the 40 and 45 year olds. Predictors, regardless of age, were: female gender, reported use of hypnotics, having previously sought help because of mental distress and current smoking.
Conclusions: HSCL-10 score was related to later use of anxiolytic drugs in a dose response manner.